<a href='..'>Go up one level</a>
<a href='.'>reload index on this level</a>
<a href='../adjacentfolder/'>Go across to another folder at the same level (up one then down)</a>
<a href='./folder'>Go down one level</a>
<a href='../..'>Go up two levels</a>
<a href='/'>Go up to html_root</a>
<a href='/folder'>Go to folder off the html_root</a>